Important Wristwatches, Watches & Clocks

Hong Kong, Hotel Furama Kempinski, May 26, 1991

LOT 199

Longines "Weems second setting watch", Caliber, 1869 N, circa 1933, production started on 18.2. 1931 of 144 watches in silver, with silver bezel. Extremely rare, hour angle, center second, 14ct gold aviator' wristwatch.

CHF 25,000 - 30,000

HKD 125,000 - 150,000

Sold: CHF 149,250

C. massive, polished, dedicated and hinged back. D. white enamel, with painted Arabic numerals at the center, revolving "mat silver" dial to adjust the time in seconds. "Breguet" blued steel hands. M. 16 3/4"' rhodiumed, "fausses côtes" decoration, 15 jewels, lever escapement, cut bimetallic balance adjusted to isochronism, Breguet balance-spring, micrometer regulator. Dial, case and movement signed. In very good condition. Diam. 41 mm


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Notes

Note. This watch in 14ct gold is an American Case probably unique, and must have been produced by AW case makers on a special request. This hour angle system is called the " Weems Model" because of its Inventor: Professor and Instructor Philippe Vanhorn Weems, of the Naval Academy of Annapolis, who was an Authority in the 1920-1930's. He formed the famous Charles A. Lindbergh who established the record for the first non-stop transoceanic flight. The hour angle watch "Lindbergh model" used for this flight is drawn from the Weems invention. Professor Ph. Weems wrote several important books and received a Gold Medal from the International Aeronautic Federation. This watch bears a large ball-shaped windingcrown, enabling the watch to be rewound by a pilot whilst wearing gloves. It is practically impossible to build a commercial timepiece which will keep time to the exact second under the conditions met in a ship or in an airplane. The unavoidable variation in the chronometer from true time has necessitated an extra calculation in navigation to compensate for this chronometer error. Lt. Commander P.V.H. Weems, U.S.N. saw that in an airplane moving at speeds of 200 to 300 miles an hour or more the time required for calcula ting chronometer error was hazard that should be eliminated. Since it is impractical because of high gear ratio to set the second hand to the dial, Commander Weems hir upon the idea of setting the dial to the hands. The seconds dial in the center of the large watch is rotated by the small stem. On marked on the outer bezel which is rotated by hand and then locked into position by an outer stem. USE: The hour and minute is set on the watch in the usual way. For navigation purposes the Greenwich Civil time is set directléy on the watch face. When being set with a radio time signal which cornes in on the minute, the second dial is rotated to keep the 60 mark continuously under the second hand. The dial is stopped the instant the signal is heard. For serious navigation, a record should he kept of the errors and of the daily rate as indicated by movement of the second dial. The Longines Weems Second-Setting Watch is made in two styles. The smaller model is useful not only for sea and air navigators and airline pilots, but particularly for those working in radio broadcasting and others, such as civil engineers requiring exact time.